In known methods of inkjet printing, droplets of ink are deposited onto a substrate using a print head. The deposited ink is then dried or cured on the substrate. In recent times, UV-curable ink compositions have been used. Such inks are cured upon exposure to UV radiation. Typically, the UV radiation used to cure such inks is produced using mercury vapour lamps. Such lamps can be employed to produce UV light covering a broad spectrum of wavelengths.
LED's are a cost-effective and safe source of UV radiation. Compared to mercury vapour lamps, however, LED sources tend to produce UV light covering a much narrower spectrum of wavelengths.